The carefully planned killing of a former prison officer simply for doing his job has "horrified" the profession and damaged morale, according to a union chief.
Lenny Scott, 33, was shot dead in February 2024 by drug-dealer Elias Morgan, four years after exposing the career criminal's sexual affair with a female officer in HMP Altcourse, Liverpool.
Attacks on staff in UK prisons reached a new peak in March this year with 10,568 assaults in the previous 12 months.
But according to Mark Fairhurst, the chairman of union the Prison Officer's Association (POA), the murder of a former officer outside the workplace was greeted by "shock and horror throughout the entire profession".
"We're all subject to threats because of the risks we face, both inside the workplace and when we're socialising," he told the BBC.
"But for this to happen, three years after someone's left the job is unprecedented."
Mr Scott was a physically imposing man into body-building, jiu-jitsu and strongman sports, so was often the go-to officer if there was trouble at the privately run Category B prison, according to detectives at Lancashire Police.
But he was also described as a "bit of a renaissance man" when it came to the rehabilitation of prisoners, keen to help inmates use exercise to help them deal with addiction or mental health issues.
According to his family, he became disillusioned about his career in March 2020 when he found himself on the receiving end of Morgan's rage after seizing an iPhone from his cell, which contained details of the affair with prison officer Sarah Williams.
A nine-week trial at Preston Crown Court heard that after refusing a £1,500 cash bribe to "lose" the phone, Mr Scott was threatened, and to his terror realised that Morgan had obtained details about his address, his partner and his children.
Mr Scott's parents, Neil and Paula Scott, have said they believed Altcourse managers did not treat those threats seriously enough.
In court, a statement from Paula described how her son told her he believed Morgan had obtained those details from the female prison officer he had been seeing, although there was no evidence to prove it.
During the trial, the jury heard prison intelligence logs recorded how Morgan had a history of threatening "grave violence", including death threats, to coerce fellow inmates and prison staff, dating back to 2011.
The logs stated that Morgan claimed he would make contact with "people in the community" who would carry out his threats on his behalf "with a variety of weapons".
On 8 February 2024, a month after staking out Mr Scott's home and two gyms he trained at, he ambushed his victim outside a gym on Peel Road in Skelmersdale, Lancashire.
Mr Scott was shot six times including in the head and was beyond help by the time paramedics arrived.
Morgan, from Edge Hill in Liverpool, was on Friday convicted of murder and will be sentenced on Tuesday 2 September.
Mr Fairhurst said: "I've never come across this sort of threat, which is carried out to such an extent, especially when someone's left the job for such a long period."
"We have what's called Osman warnings from the police, where staff are under serious and imminent risk from criminal gangs, but I've never known any member of staff to be targeted in such a way."
"It's absolutely horrific and demonstrates to the general public what a risky and unsafe job this really is."
Asked about the impact on morale, he told the BBC: "It makes you reconsider your career."
"Is it really worth the risk for the money you're getting paid because it's not a well paid job."
"You're in a hostile and violent environment and now when you're socialising outside of work or going about your daily activities out of the workplace you're even under threat then."
He echoed the concerns raised by Mr Scott's parents and said he believed the prison service's private sector needed to do more to deal with serious threats.
Mr Fairhurst said public sector prisons have procedures and policies in place to protect staff and remove them from dangerous situations.
"I'm hoping this whole sorry affair is a learning curve for the private sector to improve their processes and learn from the public sector on how we protect our staff," he said.
Sodexo, the company contracted to run Altcourse by the Ministry of Justice since it took over from G4S in 2023, said in a statement: "Our prison community has been devastated by the tragic death of our former colleague, Lenny Scott, and our deepest sympathies are with his family and friends.
"HMP Altcourse has been operated by a new provider since 2023 and is committed to continuously improving processes to safeguard our colleagues."